title: Accuracy of ankle-brachial index obtained by automated blood pressure measuring devices in patients with diabetes mellitus.
abstract: BACKGROUND
  Upper arm automated blood pressure devices are widely available and could be used to estimate the ankle-brachial index.
  
  
  METHODS
  We conducted a trial to determine the equivalence of ankle-brachial index estimated by an upper arm blood pressure measuring device as index method compared to the handheld Doppler method as the reference standard. A total of 110 patients with diabetes mellitus were sequentially examined by two methods.
  
  
  RESULTS
  The prevalence of peripheral arterial disease was 32%. The index method obtained valid measurements in 104 (95%) patients. Ankle-brachial index was lower with the index method compared to the reference standard (mean difference: -0.05; 95% confidence interval [CI]: -0.50 to 0.39). This confidence interval was above the boundaries clinically established as equivalence margins in our study. The kappa agreement between two methods was 0.45. The performance of the index method was: sensitivity: 67%; specificity: 87%; positive likelihood ratio: 5.25; negative likelihood ratio: 0.18; positive predictive value: 71%; negative predictive value: 85%; and the area under the receiving operating characteristic curve: 0.87 (95% CI: 0.78-0.93).
  
  
  CONCLUSIONS
  Upper arm automated blood pressure measuring devices cannot replace the handheld Doppler method to estimate the ankle-brachial index in patients with diabetes mellitus.
authors.affiliation: Department of Internal Medicine, Division of General Internal Medicine, Hospital Marina Baixa, Villajoyosa, Alicante, Spain. ena_jav@gva.es
authors.forename: Javier
authors.initials: J
authors.lastname: Ena
authors.forename: Teresa
authors.initials: T
authors.lastname: Lozano
authors.forename: Gema
authors.initials: G
authors.lastname: Verdú
authors.forename: Carlos R
authors.initials: CR
authors.lastname: Argente
authors.forename: Victor L
authors.initials: VL
authors.lastname: González
mesh_terms: D000368:Aged; D055109:Ankle Brachial Index; D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination / Q000379:methods; D003920:Diabetes Mellitus / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged